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1.
Antioxidants (Basel) ; 11(9)2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36139762

RESUMEN

Exercise has beneficial effects on energy balance and also improves metabolic health independently of weight loss. Adipose tissue function is a critical denominator of a healthy metabolism but the adaptation of adipocytes in response to exercise is insufficiently well understood. We have previously shown that one aerobic exercise session was associated with increased expression of antioxidant and cytoprotective genes in white adipose tissue (WAT). In the present study, we evaluate the chronic effects of physical exercise on WAT redox homeostasis and mitochondrial function. Adult male Wistar rats were separated into two groups: a control group that did not exercise and a group that performed running exercise sessions on a treadmill for 30 min, 5 days per week for 9 weeks. Reactive oxygen species (ROS) generation, antioxidant enzyme activities, mitochondrial function, markers of oxidative stress and inflammation, and proteins related to DNA damage response were analyzed. In WAT from the exercise group, we found higher mitochondrial respiration in states I, II, and III of Complex I and Complex II, followed by an increase in ATP production, and the ROS/ATP ratio when compared to tissues from control rats. Regarding redox homeostasis, NADPH oxidase activity, protein carbonylation, and lipid peroxidation levels were lower in WAT from the exercise group when compared to control tissues. Moreover, antioxidant enzymatic activity, reduced glutathione/oxidized glutathione ratio, and total nuclear factor erythroid-2, like-2 (NFE2L2/NRF2) protein levels were higher in the exercise group compared to control. Finally, we found that exercise reduced the phosphorylation levels of H2AX histone (γH2AX), a central protein that contributes to genome stability through the signaling of DNA damage. In conclusion, our results show that chronic exercise modulates redox homeostasis in WAT, improving antioxidant capacity, and mitochondrial function. This hormetic remodeling of adipocyte redox balance points to improved adipocyte health and seems to be directly associated with the beneficial effects of exercise.

2.
Intervirology ; 56(4): 249-52, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23652381

RESUMEN

OBJECTIVE: Polyomavirus-associated nephropathy (PVAN) is a major cause of graft dysfunction after kidney transplantation. Therefore, routine screening for BK polyomavirus (BKV) infection with urine cytology or quantitative PCR-based assays has been recommended. Although less expensive than quantitative tests, qualitative PCR assays are not recommended for screening based on the assumption that their diagnostic accuracy is inferior to urine cytology. However, studies comparing the performance of both methods are scarce. METHODS: We compared the accuracy between a qualitative seminested PCR (snPCR) assay and urine cytology for the screening of BKV viruria in 104 renal transplant recipients. RESULTS: The snPCR assay was more sensitive than cytology (100 and 61%, respectively), yielding better negative predictive value (100 vs. 90%). In 7 (39%) of the 18 PVAN cases, BKV infection was detected exclusively by snPCR. Although the specificity of snPCR (63%) was lower than cytology (74%), their positive predictive values were similar (36 vs. 33%, respectively). In ROC curve analysis, the accuracy of snPCR was significantly higher (p = 0.03). CONCLUSION: This qualitative snPCR assay was more accurate than urine cytology for the detection of BKV viruria in renal transplant patients.


Asunto(s)
Virus BK/aislamiento & purificación , Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena de la Polimerasa/métodos , Infecciones por Polyomavirus/diagnóstico , Orina/virología , Virología/métodos , Virus BK/genética , Humanos , Trasplante de Riñón , Tamizaje Masivo/métodos , Infecciones por Polyomavirus/virología , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Orina/citología
3.
Biochem Pharmacol ; 84(8): 1014-23, 2012 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-22796565

RESUMEN

Thrombospondin-1 (TSP-1) gives rise to fragments that have both pro- and anti-angiogenic effects in vitro and in vivo. The TSP-HepI peptide (2.3 kDa), located in the N-terminal domain of TSP-1, has proangiogenic effects on endothelial cells. We have previously shown that TSP-1 itself exhibits a dual effect on endothelial colony-forming cells (ECFC) by enhancing their adhesion through its TSP-HepI fragment while reducing their proliferation and differentiation into vascular tubes (tubulogenesis) in vitro. This effect is likely mediated through CD47 binding to the TSP-1 C-terminal domain. Here we investigated the effect of TSP-HepI peptide on the angiogenic properties of ECFC in vitro and in vivo. TSP-HepI peptide potentiated FGF-2-induced neovascularisation by enhancing ECFC chemotaxis and tubulogenesis in a Matrigel plug assay. ECFC exposure to 20 µg/mL of TSP-HepI peptide for 18 h enhanced cell migration (p < 0.001 versus VEGF exposure), upregulated alpha 6-integrin expression, and enhanced their cell adhesion to activated endothelium under physiological shear stress conditions at levels comparable to those of SDF-1α. The adhesion enhancement appeared to be mediated by the heparan sulfate proteoglycan (HSPG) syndecan-4, as ECFC adhesion was significantly reduced by a syndecan-4-neutralising antibody. ECFC migration and tubulogenesis were stimulated neither by a TSP-HepI peptide with a modified heparin-binding site (S/TSP-HepI) nor when the glycosaminoglycans (GAGs) moieties were removed from the ECFC surface by enzymatic treatment. Ex vivo TSP-HepI priming could potentially serve to enhance the effectiveness of therapeutic neovascularisation with ECFC.


Asunto(s)
Endotelio Vascular/citología , Neovascularización Fisiológica/fisiología , Trombospondina 1/fisiología , Animales , Células Cultivadas , Femenino , Citometría de Flujo , Humanos , Ratones , Trombospondina 1/química
4.
Acta Cir Bras ; 25(1): 2-8, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20126879

RESUMEN

PURPOSE: To analyze the small intestinal mucosa ultrastructure, and to characterize the enterocyte lesion severity caused by mechanical intestinal obstruction combined or not with an ischemia of the mesenteric marginal vessels arch. METHODS: It was used 47 Wistar rats divided into 4 groups as follows: Group 1- Control rats (C), Group 2- sham rats (S), Group 3- rats submitted to intestinal obstruction excluding marginal vessel (OEV), Group 4- Intestinal obstruction including marginal vessels (OIV). Rats of groups 3 and 4 were allotted into two subgroups for the removal of small intestinal tissue samples, one at the proximal (P), and the other at the distal (D) segments from the obstruction site. Samples of groups 2, 3, 4 were obtained 24, 48, and 72 hours after post operation care. Small intestinal tissue samples of group 1 were excised following laparotomy. Imaging in Light and Transmission Electronic Microscopy were used for morphological and morphometric studies. The results were analyzed by using the ANOVA and Newman-Keuls tests. RESULTS: No irreversible lesion was observed. In the 24 hours microvilli volume of group 3 turned down at the proximal site henceforth enlarging very slowly within the next 72 hours. At the distal site significant microvilli shrinkage was observed up to 48 hours. Then they recovered their volume after 72 hours. In the 24 hours microvilli volume of group 4 grew twice in comparison with the microvilli of group 1 rats but after 72 hours there was drastic volume shrinkage, shape alterations, and severe flatness, especially in the distal segments of the obstruction site. CONCLUSIONS: Terminal ileum mechanical obstruction with mesenteric marginal arch ischemia led to reversible ultrastructural alterations after 72 hours, and the injury is proportional to the persistence of the obstructive process. Furthermore the mesenteric vessels of the marginal arcade play an important role in the maintenance of mucosal integrity, when such obstructive disorder is present.


Asunto(s)
Enterocitos/ultraestructura , Mucosa Intestinal/patología , Obstrucción Intestinal/patología , Análisis de Varianza , Animales , Obstrucción Intestinal/complicaciones , Masculino , Modelos Animales , Distribución Aleatoria , Ratas , Ratas Wistar
5.
Acta cir. bras ; 25(1): 2-8, jan.-fev. 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-537134

RESUMEN

PURPOSE: To analyze the small intestinal mucosa ultrastructure, and to characterize the enterocyte lesion severity caused by mechanical intestinal obstruction combined or not with an ischemia of the mesenteric marginal vessels arch. METHODS: It was used 47 Wistar rats divided into 4 groups as follows: Group 1- Control rats (C), Group 2- sham rats (S), Group 3- rats submitted to intestinal obstruction excluding marginal vessel (OEV), Group 4- Intestinal obstruction including marginal vessels (OIV). Rats of groups 3 and 4 were allotted into two subgroups for the removal of small intestinal tissue samples, one at the proximal (P), and the other at the distal (D) segments from the obstruction site. Samples of groups 2, 3, 4 were obtained 24, 48, and 72 hours after post operation care. Small intestinal tissue samples of group 1 were excised following laparotomy. Imaging in Light and Transmission Electronic Microscopy were used for morphological and morphometric studies. The results were analyzed by using the ANOVA and Newman-Keuls tests. RESULTS: No irreversible lesion was observed. In the 24 hours microvilli volume of group 3 turned down at the proximal site henceforth enlarging very slowly within the next 72 hours. At the distal site significant microvilli shrinkage was observed up to 48 hours. Then they recovered their volume after 72 hours. In the 24 hours microvilli volume of group 4 grew twice in comparison with the microvilli of group 1 rats but after 72 hours there was drastic volume shrinkage, shape alterations, and severe flatness, especially in the distal segments of the obstruction site. CONCLUSIONS: Terminal ileum mechanical obstruction with mesenteric marginal arch ischemia led to reversible ultrastructural alterations after 72 hours, and the injury is proportional to the persistence of the obstructive process. Furthermore the mesenteric vessels of the marginal arcade play an important role in the maintenance of mucosal integrity, ...


OBJETIVO: Analisar as alterações ultra-estruturais da mucosa do intestino delgado e caracterizar a severidade das lesões causadas por uma obstrução intestinal mecânica, associada ou não a isquemia da arcada marginal mesentérica. MÉTODOS: Foram utilizados 47 ratos, da linhagem Wistar, distribuídos em quatro grupos, da seguinte forma: Grupo 1 - Controle (C), Grupo 2- Simulação (S), Grupo 3- Ratos com obstrução intestinal sem inclusão de vaso marginal (OEV), Grupo 4 - Obstrução intestinal com inclusão de vaso marginal (OIV). Os animais dos grupos 3 e 4 foram redistribuídos em dois subgrupos com coleta de amostras do intestino delgado, à montante (P) e à jusante (D) do ponto de obstrução. Nos grupos 2, 3 e 4, as amostras foram colhidas com 24, 48 e 72 horas de pós-operatório. No grupo 1, este material foi retirado após laparotomia. Realizaram-se estudos morfológicos e morfométricos dos microvilos através das Microscopias Óptica e Eletrônica de Transmissão. Os resultados foram analisados mediante os testes estatísticos de ANOVA e Newman-Keuls. RESULTADOS: Não foram observadas lesões irreversíveis. No grupo 3 com 24 horas, o volume dos microvilos diminuiu, à montante, com discreto aumento em 72 horas. Á jusante, houve redução significante até 48 horas, com recuperação em 72 horas. No grupo 4, o volume dos microvilos quase dobrou em relação ao grupo 1, com 24 horas, mas reduziu-se, drasticamente, em especial à jusante, com 72 h de evolução, apresentando deformidade e achatamento severos, achados estes estatisticamente significantes. CONCLUSÕES: A obstrução intestinal mecânica do íleo terminal, associada ou não a isquemia da arcada mesentérica marginal, causa alterações ultra-estruturais reversíveis dos enterócitos, cuja gravidade é diretamente proporcional à duração do processo mórbido obstrutivo, até 72 horas de evolução. Aduz-se que, os vasos mesentéricos da arcada marginal exercem um papel relevante na preservação da mucosa intestinal, na ...


Asunto(s)
Animales , Masculino , Ratas , Enterocitos/ultraestructura , Mucosa Intestinal/patología , Obstrucción Intestinal/patología , Análisis de Varianza , Obstrucción Intestinal/complicaciones , Modelos Animales , Distribución Aleatoria , Ratas Wistar
6.
An. bras. dermatol ; 81(5): 465-472, set.-out. 2006. ilus
Artículo en Portugués | LILACS | ID: lil-441163

RESUMEN

Em oncologia cutânea depara-se freqüentemente com situações em que a confecção de um enxerto é uma boa alternativa para o fechamento do defeito cirúrgico. Conhecer aspectos referentes à integração e contração dos enxertos é fundamental para que os cirurgiões dermatológicos procedam de maneira a não contrariar princípios básicos do transplante de pele. Os autores fazem uma revisão da classificação e fisiologia dos enxertos de pele, acrescendo considerações cirúrgicas determinantes para o sucesso do procedimento.


In cutaneous oncology, there are many situations in which skin grafts could be a good alternative for closing surgical defect. Dermatological surgeons should have enough knowledge about graft integration and contraction in order to not contradict the basic principles of skin transplantation. The authors review skin graft classification and physiology and make some surgical considerations on successful procedures.

7.
Rev. Col. Bras. Cir ; 32(4): 178-182, jul.-ago. 2005. ilus, graf
Artículo en Portugués | LILACS | ID: lil-417997

RESUMEN

OBJETIVO: Relacionar as alterações morfológicas renais sob microscopia de luz, de ratos submetidos à oclusão de aorta, em modelo que simule a condição clínica de reparação cirúrgica de um aneurisma de aorta abdominal. MÉTODO: Ratos Wistar (N = 60), machos pesando entre 200 e 250g, foram distribuídos em três grupos: I (simulado); II (isquemia); III (isquemia + reperfusão); e cada grupo redistribuído em dois subgrupos: A (30 min); B (60 min). Foi realizada isquemia utilizando clamp vascular (8mm) na aorta abdominal infra-renal de acordo com o grupo estudado. Ao final de cada experimento os animais foram mortos e realizada análise histológica renal cortical e medular (descritiva e morfométrica) através de metodologia convencional (parafina-hematoxilinaeosina). A análise semiquantitativa de lesão tubular e intersticial foi realizada de acordo com o índice de lesão tubular e índice de lesão intersticial. Para a análise estatística foram aplicados os seguintes testes: Mann-Whitney, Kruskal-Wallis, Comparações múltiplas (p < 0,001). RESULTADOS: Observou-se no grupo III alterações histológicas tubulares e intersticiais significantes com relação aos outros grupos (p < 0,001). CONCLUSÕES: A oclusão da aorta abdominal infra-renal em ratos está associada a lesões estruturais renais tanto tubulares quanto intersticiais principalmente na fase de reperfusão.

8.
Mem Inst Oswaldo Cruz ; 97 Suppl 1: 165-6, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12426613

RESUMEN

The study had the objective to evaluate the benefits of surgical indication for portal hypertension in schistosomiasis patients followed from 1985 to 2001. Schistosoma mansoni eggs were confirmed by at least six stool examinations or rectal biopsy. Clinical examination, abdominal ultrasonography, and digestive endoscopy confirmed the diagnosis of esophageal varices. A hundred and two patients, 61.3% male (14-53 years old) were studied. Digestive hemorrhage, hypersplenism, left hypochondrial pain, abdominal discomfort, and hypogonadism were, in a decreasing order, the major signs and symptoms determining surgical indication. Among the surgical techniques employed, either splenectomy associated to splenorenal anastomosis or azigoportal desvascularization, esophageal gastric descompression and esophageal sclerosis were used. Follow-up of patients revealed that, independent on the technique utilized, a 9.9% of death occurred, caused mainly by digestive hemorrhage due to the persistence of post-treatment varices. The authors emphasize the benefits of elective surgical indication allowing a normal active life.


Asunto(s)
Hipertensión Portal/cirugía , Esquistosomiasis mansoni/cirugía , Adolescente , Adulto , Várices Esofágicas y Gástricas/etiología , Várices Esofágicas y Gástricas/cirugía , Femenino , Estudios de Seguimiento , Hemorragia Gastrointestinal/etiología , Humanos , Hipertensión Portal/parasitología , Masculino , Persona de Mediana Edad , Esquistosomiasis mansoni/complicaciones , Esplenectomía , Enfermedades del Bazo/cirugía , Resultado del Tratamiento
9.
Mem. Inst. Oswaldo Cruz ; 97(suppl.1): 165-166, Oct. 2002.
Artículo en Inglés | LILACS | ID: lil-325037

RESUMEN

The study had the objective to evaluate the benefits of surgical indication for portal hypertension in schistosomiasis patients followed from 1985 to 2001. Schistosoma mansoni eggs were confirmed by at least six stool examinations or rectal biopsy. Clinical examination, abdominal ultrasonography, and digestive endoscopy confirmed the diagnosis of esophageal varices. A hundred and two patients, 61.3 percent male (14-53 years old) were studied. Digestive hemorrhage, hypersplenism, left hypochondrial pain, abdominal discomfort, and hypogonadism were, in a decreasing order, the major signs and symptoms determining surgical indication. Among the surgical techniques employed, either splenectomy associated to splenorenal anastomosis or azigoportal desvascularization, esophageal gastric descompression and esophageal sclerosis were used. Follow-up of patients revealed that, independent on the technique utilized, a 9.9 percent of death occurred, caused mainly by digestive hemorrhage due to the persistence of post-treatment varices. The authors emphasize the benefits of elective surgical indication allowing a normal active life


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Adolescente , Hipertensión Portal , Esquistosomiasis mansoni , Várices Esofágicas y Gástricas , Estudios de Seguimiento , Hemorragia Gastrointestinal , Hipertensión Portal , Esquistosomiasis mansoni , Esplenectomía , Enfermedades del Bazo , Resultado del Tratamiento
10.
An. bras. dermatol ; 73(4): 327-32, jul.-ago. 1998. ilus
Artículo en Inglés | LILACS | ID: lil-226507

RESUMEN

Relato de caso infreqüente de granuloma eosinofílico, a forma localizada da histiocitose de células de Langerhans, em paciente masculino de 24 anos com envolvimento cutâneo e pulmonar. A síndrome histiocítica é um grupo de alteraçöes proliferativas das células histocíticas que expressam o fenótipo de células de Lagerhans. Varia da forma benigna localizada a fatal e disseminada com envolvimento multicêntrico. Duas categorias foram recentemente estabelecidas: histiocitose de células de Langerhans e histiocitose de células näo-Langerhans. Os autores discutem os aspectos clínicos, histológicos, imunohistoquímicos e ultraestruturais desta forma rara de histiocitose, que pode lembrar várias outras condiçöes, como doença de Darier, dermatite seborréica e psoríase


Asunto(s)
Humanos , Masculino , Adulto , Células de Langerhans/ultraestructura , Granuloma Eosinófilo/patología , Histiocitosis de Células de Langerhans/patología , Diagnóstico Diferencial , Histiocitosis/diagnóstico , Inmunohistoquímica , Neumonía/diagnóstico , Eosinofilia Pulmonar
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